Major Depressive Disorder in Adults

The word depression is used to describe various and sometimes overlapping experiences. To many people being depressed means feeling sad, ‘blue’, downhearted, disappointed, detached or upset. However, a person can feel all these emotions without being ‘clinically’ depressed. Feelings of sadness or the ‘blues’ are generally brief and have slight effects on normal functioning.

Clinical depression is an emotional, physical and cognitive (thinking) state that is intense and long-lasting and has more negative effects on a person’s day-to-day life. Approximately one in five people will experience an episode of clinical depression in their lifetime.

It is also important to distinguish depression from the sadness we naturally experience after loss, such as during bereavement. Although the grief associated with loss is often intense and long lasting, such emotions are a healthy response to loss and allow people to adjust to their new life circumstances. Depression on the other hand, can have significant and detrimental effects on many aspects of a person’s life. It is generally important to consider what is causing and maintaining the depression for improvement to take place. This may involve a person approaching life stresses or relationships differently, making lifestyle changes, regaining self-esteem or reconnecting with his or her values.

Causes

Hereditary – There is evidence that some people have a genetic predisposition to developing depression. Having a family history of depression does not mean that a person will necessarily develop depression, but it does mean that the risk of developing depression can be higher than if there is no family history. There are usually other situational factors involved such as a stressful life event or chronic illness that may act as a trigger for the onset of a depressive episode.

Biochemical – People who are depressed demonstrate abnormal functioning of some chemicals in the brain. Neurotransmitters are naturally occurring chemicals that send signals from one part of the brain to the next. In people who are depressed the mood-regulating neurotransmitters do not function normally, which interferes with signals sent to the brain and causes mood to be affected.

Stress – Stressful life events can act as a trigger for depression. While most people will experience some level of depressed mood following a stressful event such as a relationship break-up, this often reduces over time. However, for some people the depressed mood will persist and lead to clinical depression. There is evidence that life events that put a person at a higher risk for depression are those that impact on the person’s self-esteem, such as experiencing a relationship breakdown or a financial or job loss.

Personality – Some personality types are more likely to develop depression. There is evidence that people who experience high anxiety levels, are very sensitive to criticism, or have a perfectionist personality have a higher risk of developing depression.

Symptoms

Loss of interest in pleasurable activities and daily routine – People who experience depression are often unable to complete daily tasks and do not enjoy activities they previously took pleasure in. They miss out on positive experiences associated with a sense of achievement and on the pleasure derived from completing daily tasks. The people around them may also suffer as a result.

Worrying and negative thinking – People with depression often worry about the future and have negative thoughts about themselves and their circumstances. These thinking patterns are very unhelpful in that they reduce a person’s ability to focus on recovery and tend to increase their vulnerability to other unhealthy emotions and behaviours.

Irritability, agitation and fatigue – People with depression often experience irritability and agitation, and may complain of exhaustion. Sometimes they feel frustrated with their rate of recovery or the level of support available and annoyed that they don’t have the energy to do anything. They may become more easily upset with those around them. Irritability, agitation and fatigue are often made worse by changes in sleeping patterns and other symptoms associated with depression, such as negative thinking.

Changes in sleeping patterns – Changes in sleeping patterns (either sleeping too much or having trouble sleeping) are common in individuals experiencing depression. Disruptive sleeping patterns can make a person feel worse and make routine communication and activities seem overly difficult and frustrating.